Solving system of equations

(1) 4x+2y=24

(2) 2x-8y=-6

(3) Y=6X-3

(4) 2Y=-6X+6

(5) X = 3y +4

(6) 2x-18y = 2

(7) 2x + y = 9

(8) 3x – y = 16